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GB/T 2481.1-1998 Testing and marking of abrasive grain composition for bonded abrasives Part 1: Coarse abrasive grains F4~F220

Basic Information

Standard ID: GB/T 2481.1-1998

Standard Name: Testing and marking of abrasive grain composition for bonded abrasives Part 1: Coarse abrasive grains F4~F220

Chinese Name: 固结磨具用磨料 粒度组成的检测和标记 第1部分: 粗磨粒F4~F220

Standard category:National Standard (GB)

state:in force

Date of Release1998-01-01

Date of Implementation:1999-09-01

standard classification number

Standard ICS number:Mechanical manufacturing>> cutting tools>> 25.100.70 Abrasives and grinding tool testing>> 19.120 Particle size analysis, screening

Standard Classification Number:Machinery>>Process Equipment>>J43 Abrasives and Grinding Tools

associated standards

alternative situation:Part of GB 2477-1983 Part of GB 2481-1983

Procurement status:eqv ISO 8486-1:1996

Publication information

publishing house:China Standards Press

ISBN:155066.1-15648

Publication date:1999-08-01

other information

Release date:1981-02-17

Review date:2004-10-14

drafter:Bao Hua, Fu Fengli, Xiang Zuren, Chen Deguang

Drafting unit:Zhengzhou Abrasives Institute

Focal point unit:National Technical Committee for Standardization of Abrasives and Grinding Tools

Proposing unit:Ministry of Machinery Industry of the People's Republic of China

Publishing department:State Administration of Quality and Technical Supervision

competent authority:China Machinery Industry Federation

Introduction to standards:

This standard specifies the particle size composition and detection method of corundum and silicon carbide abrasives, F4~F22 coarse abrasive grains, and specifies the particle size marking method. This standard is applicable to abrasive grains used in the manufacture of bonded abrasives and general industrial purposes, as well as abrasive grains recovered from bonded abrasives. GB/T 2481.1-1998 Detection and marking of particle size composition of abrasives for bonded abrasives Part 1: Coarse abrasive grains F4~F220 GB/T2481.1-1998 Standard download decompression password: www.bzxz.net

Some standard content:

ICS25.100.70;19.120
National Standard of the People's Republic of China
GB/T2481.1—1998
eqvIs08486-1:1996
Abrasives for bonded abrasives
Detection and designation of grain size distribution
Part 1: Macrogrits F4 to F220
Bonded abrasives-Determination and designationof grain size distribution-
Part 1: Macrogrits F4 to F220 F2201998-11-18 Issued
1999-09-01 Implementation
State Administration of Quality and Technical Supervision
People's Republic of China
National Standard
Abrasives for bonded abrasives
4 Detection and marking of grain size composition
Part 1: Coarse abrasive grains F4 to F220
GB/T2481.1-1998
Published by China Standards Press
No. 16, Sanlihebei Street, Fuxingmenwai, Beijing
Postal Code: 100045
Tel: 68522112
Printed by China Standards Press, Qinhuangdao Printing Factory, Xinhua Bookstore, Beijing Distribution Office Sold by Hua Bookstore, no reprinting allowed
Copyright reserved
Format 880×12301/16
First edition in April 1999
Printing sheet 3/4
Word count 18,000 words
First printing in April 1999
Print run 1-800
Book number: 155066·1-15648
Price 8.00 yuan
Heading 370-02
GB/T2481.1-1998
This standard equivalently adopts the international standard ISO8486-1:1996 "Testing and marking of abrasive grain size composition for bonded abrasives Part 1: Coarse abrasive grains F4~F220". The particle size composition and marking are consistent with the international standards, and the testing conditions and methods are basically the same, which is conducive to international trade. However, due to the differences in the test sieve hole size and screening conditions, a large deviation will occur. Therefore, this standard proposes a method of correcting the screening value with standard sand to achieve uniform and accurate particle size composition test results. This standard is consistent with the international standards in terms of editing. This standard is based on the principle of actively adopting international standards and foreign advanced standards, and revises the coarse abrasive part of GB2477-83 "Abrasive Grain Size and Composition" and GB2481-83 "Abrasive Grain Size Composition Determination Method". This revision includes the coarse abrasive part that originally belonged to GB2477-83 and GB2481-83 into this standard, and the particle size marking and particle size composition marking method using the test sieve have changed greatly, the requirements for the test sieve have been tightened, the allowable deviation of the particle size composition has been increased, the F240 particle size number has been cancelled, and it has been included in the micro powder series. From the date of implementation, this standard will replace the medium and coarse abrasive grains of GB2477-83 and GB2481-83. The general title of GB/T2481-1998 is "Abrasives for bonded abrasives Part 1: Coarse abrasive grains F4-F220
Part 2: Micro powder F230-F1200
Appendix A of this standard is the appendix of the standard.
This standard is proposed by the Ministry of Machinery Industry of the People's Republic of China. This standard is under the jurisdiction of the National Technical Committee for Standardization of Abrasives and Grinding Tools. Detection and marking of particle size composition", and consists of the following parts: The responsible drafting unit of this standard: Zhengzhou Abrasives and Grinding Research Institute. Participating drafting units: Qisha Group Co., Ltd., Baige (Group) Co., Ltd.
The main drafters of this standard: Bao Hua, Fu Fengli, Xiang Zuren, Chen Deguang. 1
GB/T2481.1-1998
ISO Foreword
ISO (International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The formulation of international standards is usually carried out through ISO technical committees. Each member body interested in a particular profession has the right to participate in the technical committee of that profession. International organizations, whether governmental or non-governmental, that have ties to ISO also participate in its work. ISO has close ties with the International Electrotechnical Commission (IEC) in all aspects of electrotechnical standardization. The draft international standards adopted by the technical committees are voted on by the member bodies. The standard can only be published as an international standard if at least 75% of the member bodies participating in the vote agree.
International standard ISO8486-1 was formulated by ISO/TC29 (Small Tools Technical Committee)/SC5 (Abrasives Subcommittee). This standard ISO 8486-1 revises and replaces ISO 8486:1986. The general title of ISO 8486 is "Detection and designation of grain size distribution for bonded abrasives" and consists of the following parts: - Part 1: Macrogrits F4 to F220
Part 2: Micropowders F230 to F1200
National Standard of the People's Republic of China
Determination and designation of grain size distribution for bonded abrasives Part 1: Macrogrits F4 to F220
Bonded abrasives-Determination and designationof grain size distribution-
Part 1: Macrogrits F4 to F220 F2201 Scope
GB/T2481.1—1998
eqvIso8486-1:1996
Replaces GB2477--83
GB2481--83
This standard specifies the composition and detection methods of coarse abrasive grains of corundum and silicon carbide, F4~F220, and specifies the grain size marking method.
This standard is applicable to abrasive grains used in the manufacture of bonded abrasives and general industrial purposes, as well as abrasive grains recovered from bonded abrasives. 2 Referenced standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T4676-1984 Sampling method for common abrasives GB/T6003.1-1997 Metal woven wire mesh test sieve GB/T16458.1-1996 Terminology of abrasives and grinding tools Part 1: Terminology of abrasives 3 Definitions
This standard adopts the following definitions:
3.1 Abrasive grain
According to 2.2 of GB/T16458.1-1996. 3.2 Grain size composition Grain size distribution According to 2.3.2 of GB/T16458.1-1996. 4 Grain size composition detection
4.1 Device and standard sand
4.1.1 Screening machine
$200 slapping vibrating screen machine, speed 290r/min, slapping times 156 times/min, slapping height 38mm. Under the action of these two forces, the whole set of screens should be able to rotate freely. The sieve machine is equipped with a tray to support the sieve, and the cover is equipped with a soft plug. 4.1.2 Test sieves \
1) Contact the Secretariat of the National Technical Committee for Standardization of Abrasives and Grinding Tools for purchase. Address: No. 121 Huashan Road, Zhengzhou City, Postal Code: 450007, Tel: 0371-7614280. This information is provided for the convenience of users of this standard. Equivalent products that can produce the same results can be used. Approved by the State Administration of Quality and Technical Supervision on November 18, 1998 and implemented on September 1, 1999
GB/T2481.1—1998
Conforms to GB/T6003.1, the sieve frame size is $200mm×50mm, and must be calibrated with standard sand [see A3.4 in Appendix A (Appendix to the standard)].
The test sieve is marked with its mesh size. If the mesh size is less than 1mm, it is expressed in um; if the mesh size is equal to or greater than 1mm, it is expressed in mm.
4.1.3 Balance
Use a balance with a sensitivity of 0.1g.
4.1.4 Timer
Can work continuously for 5min, with an accuracy of at least 5min±5s. 4.1.5 Standard sand 1))
The standard sample used to calibrate the screening results is made of brown corundum, with a particle size of F12~F220. Each standard sand certificate is attached with its reference value.
4.2 Testing steps
4.2.1 Sampling
According to GB/T4676, take 100g of the sample to be tested that is statistically representative. The sample to be tested must be dried. The drying method is: place the sample in an oven at a temperature of 105℃, dry until constant weight, and cool it for use. 4.2.2 Configuration and installation of test sieves
Select and stack the test sieves (a total of five layers, see Table 1) according to the particle size of the sample to be tested, and place the coarsest sieve on the top, and then go down to the finest sieve in sequence. The bottom is equipped with a chassis.
Pour the sample to be tested on the top sieve and cover it with a sieve cover. Install the configured set of sieves on the sieve machine. 4.2.3 Screening
Set the sieve machine timer to 5min and start the sieve machine. After the screening is completed, move the abrasive particles left on each layer of the sieve and in the chassis to the balance pan, and weigh them one by one from the sieve of the coarsest sieve, with an accuracy of 0.1g. If the total mass of the sample after screening is less than 99.0g, it should be retested.
4.2.4 Correction with standard sand
According to Appendix A (Appendix of the standard), the screening results are corrected to obtain the correction value. 4.2.5 Test results
Repeat 4.2.1~4.2.4. The average value of the two tests is taken as the final test result of the sample to be tested. For F4F10 abrasive grains, directly use the test sieve that meets GB/T6003.1 for screening, and the screening result is taken as the test result of the sample to be tested. 5 Standard particle size classification limits
5.1 Standard particle size composition of F4~F220 coarse abrasive grains Table 1 lists the particle size classification allowable limits of corundum and silicon carbide coarse abrasive grains used for manufacturing bonded abrasive tools and as free abrasive grains. 5.2 Explanation of test results
If the test results meet Table 1, the sample is qualified. Due to the error of the test technology itself, the test results should have an allowable deviation. According to the test, the allowable deviation value is shown in Table 2. The allowable values ​​of the particle size composition of coarse abrasive products are the values ​​in Table 1 plus the values ​​in Table 2. 1) You can contact the Secretariat of the National Technical Committee for Standardization of Abrasives and Grinding Tools for purchase. This information is provided for the convenience of users of this standard. Equivalent products that can produce the same results can be used. 2
GB/T2481.1-1998
Particle size marking
Coarsest particle
GB/T2481.1-1998
Table 2 Allowable deviation of particle size composition
Note: The percentages listed are relative to the initial mass of the sample. 5.3 Application examples of Tables 1 and 2
Basic particle
Mixed particle
The following uses F20 coarse abrasive as an example to illustrate the application of this standard (the values ​​listed in the example are the corrected test values): Fine
Take F20 abrasive, and all of the abrasive should pass through the coarsest sieve (sieve opening 1.70mm). All the abrasive particles can pass through the coarse sieve (1.18 mm mesh), but the oversize of this sieve cannot exceed 20%.
The oversize of the 1.00 mm mesh should be at least 45%, but 100% of the abrasive particles are allowed to pass through the 1.18 mm mesh and remain on the 1.00 mm mesh.
The sum of the abrasive particles passing through the 1.18 mm mesh and remaining on the 1.00 mm and 850 μm meshes should be at least 70%. Therefore, if the oversize of the 1.00 mm mesh is 45%, the oversize of the 850 μm mesh should be at least 25%. The amount of material on the finest sieve (sieve opening 710μm) is not specified, but the number of abrasive grains passing through the sieve with a sieve opening of 710μm is not allowed to exceed 4
GB/T2481.1—1998
The procedure for determining the particle size composition of other particle sizes is similar. The allowable deviation values ​​in Table 2 should be included in the delivery acceptance of F20 abrasive grains. Taking coarse grains as an example, corresponding to Table 2, 20% should be increased to 24% (plus 4%), that is, the maximum coarse grain is 24%. 6 Marking
The marking of corundum and silicon carbide coarse abrasive grains that meet the requirements of this standard shall include: a) abrasive type (name or code);
b) abrasive grain marking -
consists of the letter "F" representing abrasive for bonded abrasives followed by a characteristic number representing the particle size. Silicon carbide-F80
Type of abrasive
Abrasive marking
A1 Purpose
GB/T2481.1—1998
Appendix A
(Appendix to the standard)
Standard sand correction method
According to the operating method in 4.2, due to the differences in the test sieve hole size and screening conditions, the screening results will have a large deviation. Use standard sand to correct the screening value to obtain a more accurate particle size composition test result. 2 Scope
This method is applicable to the correction of coarse particles, basic particles and mixed particles, but not to the correction of the coarsest particles and fine particles. 3 Correction method
The correction is carried out according to the following procedures:
A3.1 Prepare normal probability paper.
A3.2 Set the vertical axis of the normal probability paper as the cumulative percentage of the particle size composition, and draw vertical lines on the horizontal axis at intervals of 20 scales for the basic dimensions of the screen corresponding to the coarse particles, basic particles and mixed particles. This line is defined as the basic dimension line of the screen (see Figure A1). However, for F150, F180 and F220, the basic dimension lines of the screen corresponding to the coarse particles and basic particles are spaced 40 scales apart (see Figure A2). A3.3 Mark the reference values ​​of the standard sand on the corresponding basic dimension lines of the screen, and connect these points in turn with straight lines, which is the reference line of the standard sand.
A3.4 Use the test sieve to be calibrated to screen the standard sand according to 4.2. However, when screening the standard sand, the full amount of each portion of standard sand should be screened, and the loss of each screening should not exceed 1.0g. The cumulative percentages obtained by screening are marked on the standard sand reference line, and parallel lines of the vertical axis are drawn through each point. These parallel lines are called the effective size lines of the mesh of each layer of the test sieve. If the effective size line deviates from the basic size line by more than 7 grids, the sieve cannot be used as a test sieve for abrasive testing. A3.5 Use the same conditions as A3.4 to screen the sample to be tested, mark the cumulative percentages obtained on the effective size line, and connect two adjacent points into straight lines (see Figures A1 and A2). A3.6 Find the intersection points of these connecting lines (or the extension of the connecting lines) with each basic size line. The vertical coordinates of these intersection points are the cumulative percentage content of the sample to be tested after calibration. The particle size composition of each particle group is calculated from this, which is the test result of coarse particles, basic particles and mixed particles of the sample to be tested.
GB/T2481.1-1998
Standard sand reference line
Sample measurement line
Test sieve mesh
Effective size line
×standard sand reference value
·standard sand measurement value
. Sample measurement value
Sample correction value
Mixed particles
Basic particles
Figure A1F12~F120 Correction method for particle size1-1998
Table 2 Permissible deviation of particle size composition
Note: The percentages listed are relative to the initial mass of the sample. 5.3 Application examples of Tables 1 and 2
Basic particles
Mixed particles
The following uses F20 coarse abrasive particles as an example to illustrate the application of this standard (the values ​​listed in the example are corrected test values): Fine
Take F20 abrasive particles, and all of them should pass through the coarsest sieve (sieve opening 1.70 mm). All of the abrasive particles can pass through the coarse particle sieve (sieve opening 1.18 mm), but the amount of material on the sieve cannot exceed 20%.
The amount of material on the sieve with a sieve opening of 1.00 mm should be at least 45%, but 100% of the abrasive particles are allowed to pass through the sieve with a sieve opening of 1.18 mm and remain on the sieve with a sieve opening of 1.00 mm.
The total amount of abrasive particles passing through a sieve with a mesh size of 1.18 mm and remaining on sieves with mesh sizes of 1.00 mm and 850 μm should be at least 70%. Therefore, if the oversize on a sieve with a mesh size of 1.00 mm is 45%, the oversize on a sieve with a mesh size of 850 μm should be at least 25%. The amount of oversize on the finest sieve (mesh size of 710 μm) is not specified, but the amount of abrasive particles passing through a sieve with a mesh size of 710 μm is not allowed to exceed 4
GB/T2481.1—1998
The procedure for determining the particle size composition of other particle sizes is similar. The allowable deviation values ​​in Table 2 should be included in the delivery acceptance of F20 abrasive particles. Taking coarse particles as an example, corresponding to Table 2, 20% should be increased to 24% (plus 4%), that is, the maximum coarse particles are 24%. 6 Marking
The marking of corundum and silicon carbide coarse abrasive grains that meet the requirements of this standard shall include: a) abrasive type (name or code);
b) abrasive grain mark -
consists of the letter "F" representing abrasive for bonded abrasives followed by a characteristic number representing the grain size. Silicon carbide-F80
Abrasive type
Abrasive grain mark
A1 Purpose
GB/T2481.1—1998
Appendix A
(Standard Appendix)
Standard sand correction method
According to the operating method in 4.2, due to the differences in the test sieve hole size and screening conditions, the screening results will have a large deviation. Use standard sand to correct the screening value to obtain a more accurate particle size composition test result. 2 Scope
This method is applicable to the correction of coarse particles, basic particles and mixed particles, but not to the correction of the coarsest particles and fine particles. 3 Correction method
The correction is carried out according to the following procedures:
A3.1 Prepare the normal probability paper.
A3.2 Set the vertical axis of the normal probability paper as the cumulative percentage of the particle size composition, and draw vertical lines on the horizontal axis at intervals of 20 scales for the basic size of the sieve corresponding to the coarse particles, basic particles and mixed particles. This line is defined as the basic size line of the sieve (see Figure A1). However, for F150, F180 and F220, the basic size lines of the sieve corresponding to the coarse particles and basic particles are spaced 40 scales apart (see Figure A2). A3.3 Mark the reference values ​​of the standard sand on the corresponding basic size lines of the sieve, and connect these points in turn with straight lines, which is the reference line of the standard sand.
A3.4 Use the test sieve to be calibrated to screen the standard sand according to 4.2. However, when screening the standard sand, the full amount of each portion of standard sand should be screened, and the loss of each screening should not exceed 1.0g. The cumulative percentages obtained by screening are marked on the standard sand reference line, and parallel lines of the vertical axis are drawn through each point. These parallel lines are called the effective size lines of the mesh of each layer of the test sieve. If the effective size line deviates from the basic size line by more than 7 grids, the sieve cannot be used as a test sieve for abrasive testing. A3.5 Use the same conditions as A3.4 to screen the sample to be tested, mark the cumulative percentages obtained on the effective size line, and connect two adjacent points into straight lines (see Figures A1 and A2). A3.6 Find the intersection points of these connecting lines (or the extension of the connecting lines) with each basic size line. The vertical coordinates of these intersection points are the cumulative percentage content of the sample to be tested after calibration. The particle size composition of each particle group is calculated from this, which is the test result of coarse particles, basic particles and mixed particles of the sample to be tested.
GB/T2481.1-1998
Standard sand reference line
Sample measurement line
Test sieve mesh
Effective size line
×standard sand reference value
·standard sand measurement value
. Sample measurement value
Sample correction value
Mixed particles
Basic particles
Figure A1F12~F120 Correction method for particle size1-1998
Table 2 Permissible deviation of particle size composition
Note: The percentages listed are relative to the initial mass of the sample. 5.3 Application examples of Tables 1 and 2
Basic particles
Mixed particles
The following uses F20 coarse abrasive particles as an example to illustrate the application of this standard (the values ​​listed in the example are corrected test values): Fine
Take F20 abrasive particles, and all of them should pass through the coarsest sieve (sieve opening 1.70 mm). All of the abrasive particles can pass through the coarse particle sieve (sieve opening 1.18 mm), but the amount of material on the sieve cannot exceed 20%.
The amount of material on the sieve with a sieve opening of 1.00 mm should be at least 45%, but 100% of the abrasive particles are allowed to pass through the sieve with a sieve opening of 1.18 mm and remain on the sieve with a sieve opening of 1.00 mm.
The total amount of abrasive particles passing through a sieve with a mesh size of 1.18 mm and remaining on sieves with mesh sizes of 1.00 mm and 850 μm should be at least 70%. Therefore, if the oversize on a sieve with a mesh size of 1.00 mm is 45%, the oversize on a sieve with a mesh size of 850 μm should be at least 25%. The amount of oversize on the finest sieve (mesh size of 710 μm) is not specified, but the amount of abrasive particles passing through a sieve with a mesh size of 710 μm is not allowed to exceed 4
GB/T2481.1—1998
The procedure for determining the particle size composition of other particle sizes is similar. The allowable deviation values ​​in Table 2 should be included in the delivery acceptance of F20 abrasive particles. Taking coarse particles as an example, corresponding to Table 2, 20% should be increased to 24% (plus 4%), that is, the maximum coarse particles are 24%. 6 Marking
The marking of corundum and silicon carbide coarse abrasive grains that meet the requirements of this standard shall include: a) abrasive type (name or code);
b) abrasive grain mark -
consists of the letter "F" representing abrasive for bonded abrasives followed by a characteristic number representing the grain size. Silicon carbide-F80
Abrasive type
Abrasive grain mark
A1 Purpose
GB/T2481.1—1998
Appendix A
(Standard Appendix)
Standard sand correction method
According to the operating method in 4.2, due to the differences in the test sieve hole size and screening conditions, the screening results will have a large deviation. Use standard sand to correct the screening value to obtain a more accurate particle size composition test result. 2 ScopewwW.bzxz.Net
This method is applicable to the correction of coarse particles, basic particles and mixed particles, but not to the correction of the coarsest particles and fine particles. 3 Correction method
The correction is carried out according to the following procedures:
A3.1 Prepare the normal probability paper.
A3.2 Set the vertical axis of the normal probability paper as the cumulative percentage of the particle size composition, and draw vertical lines on the horizontal axis at intervals of 20 scales for the basic size of the sieve corresponding to the coarse particles, basic particles and mixed particles. This line is defined as the basic size line of the sieve (see Figure A1). However, for F150, F180 and F220, the basic size lines of the sieve corresponding to the coarse particles and basic particles are spaced 40 scales apart (see Figure A2). A3.3 Mark the reference values ​​of the standard sand on the corresponding basic size lines of the sieve, and connect these points in turn with straight lines, which is the reference line of the standard sand.
A3.4 Use the test sieve to be calibrated to screen the standard sand according to 4.2. However, when screening the standard sand, the full amount of each portion of standard sand should be screened, and the loss of each screening should not exceed 1.0g. The cumulative percentages obtained by screening are marked on the standard sand reference line, and parallel lines of the vertical axis are drawn through each point. These parallel lines are called the effective size lines of the mesh of each layer of the test sieve. If the effective size line deviates from the basic size line by more than 7 grids, the sieve cannot be used as a test sieve for abrasive testing. A3.5 Use the same conditions as A3.4 to screen the sample to be tested, mark the cumulative percentages obtained on the effective size line, and connect two adjacent points into straight lines (see Figures A1 and A2). A3.6 Find the intersection points of these connecting lines (or the extension of the connecting lines) with each basic size line. The vertical coordinates of these intersection points are the cumulative percentage content of the sample to be tested after calibration. The particle size composition of each particle group is calculated from this, which is the test result of coarse particles, basic particles and mixed particles of the sample to be tested.
GB/T2481.1-1998
Standard sand reference line
Sample measurement line
Test sieve mesh
Effective size line
×standard sand reference value
·standard sand measurement value
. Sample measurement value
Sample correction value
Mixed particles
Basic particles
Figure A1F12~F120 Correction method for particle size1-1998
Standard sand reference line
Sample measurement line
Test sieve mesh
Effective size line
×standard sand reference value
·standard sand measurement value
. Sample measurement value
Sample correction value
Mixed particles
Basic particles
Figure A1F12~F120 Correction method for particle size1-1998
Standard sand reference line
Sample measurement line
Test sieve mesh
Effective size line
×standard sand reference value
·standard sand measurement value
. Sample measurement value
Sample correction value
Mixed particles
Basic particles
Figure A1F12~F120 Correction method for particle size
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